Chlorosulfonic acid → 5-(Chlorosulfonyl)-2-methylbenzoic acid methyl ester

Chlorosulfonic acid (106.2 ml) was carefully added over 1 min with stirring under nitrogen to 2-methyl-benzoic acid methyl ester (55.9 ml, 0.4 mol). The reaction mixture was placed in an oil bath preheated to 100° C. for 15 min, then poured onto ice (1000 ml). The resulting precipitate was filtered and dissolved in ethyl acetate (400 ml). The ethyl acetate solution was washed sequentially with 10×300 ml saturated aqueous sodium bicarbonate, 300 ml water and 300 ml brine, dried (anhydrous sodium sulfate) and concentrated under reduced pressure to yield the title compound as a yellowish oil (37.3 g, 37% yield). 1H NMR (400 MHz, CDCl3) δ, 2.74 (s, 3H), 3.96 (s, 3H), 7.52 (d, 1H), 8.04 (m, 1H), 8.58 (d, 1H).

1. customThe reaction mixture was placed in an oil bath
2. additionpoured onto ice (1000 ml)
3. filtrationThe resulting precipitate was filtered
4. dissolutiondissolved in ethyl acetate (400 ml)
5. washThe ethyl acetate solution was washed sequentially with 10×300 ml saturated aqueous sodium bicarbonate, 300 ml water and 300 ml brine
6. dry with materialdried (anhydrous sodium sulfate)
7. concentrationconcentrated under reduced pressure

ORD record

ord-7663c7103b4846b59a4baffe8d2f44a5

Source dataset

uspto-grants-2007_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07262318B2